Question

Glass has refractive index m with respect to air and the critical angle for a ray of light going from glass to air is q. If a ray of light is incident from air on the glass with angle of incidence q, the corresponding angle of refraction is –

• A. sin^–1$\left( \frac { 1 } { \sqrt { \mu } } \right)$
• B. 90⁰
• C. sin^–1$\left( \frac { 1 } { \mu ^ { 2 } } \right)$
• D. sin^–1$\left( \frac { 1 } { \mu } \right)$

Answer 1

Answer: (C)

sin^–1$\left( \frac { 1 } { \mu ^ { 2 } } \right)$

Answer 2

_am_g =$\frac { 1 } { \sin \theta }$, m =$\frac { 1 } { \sin \theta }$ …(1)

by snell's m ==…(2)

sin r =$\frac { \sin \theta } { \mu }$ by (1) and (2)

sin r =$\frac { 1 } { \mu ^ { 2 } }$ Ž r = sin^–1$\left( \frac { 1 } { \mu ^ { 2 } } \right)$